TNMap, a new electronic map of Tennessee, is being created as a seamless, consistent, high-resolution set of digital, geospatial data products. The TNMap is being compiled from data created through the Tennessee Base Mapping Program, a seven year effort (2000-2006), to collect high-resolution aerial photography and elevation data, comprehensive cadastral (parcel) features, an intelligent street centerline database, and other planimetric features.
The TNMap’s digital files will be accessible through a web portal via web-services with no user fees and appropriate metadata search capabilities. The TNMap is part of an ambitious program of the federal government called The National Map, an effort coordinated by the United States Geological Survey (USGS) to provide the public with digital map data.
The vision for TNMap also includes leveraging existing GIS data collected and maintained by other State agencies and the federal government. Through the development of this enterprise GIS service, the TNMap will serve as the most comprehensive source for GIS data in Tennessee and will benefit many State organizations – state agencies, counties, local governments, and regional agencies. The Tennessee Base Mapping Program’s collaborative approach is based on the principle of creating spatial data once, using it for a wide range of business applications, and maintaining it using the most cost effective approach that eliminates or reduces duplication of effort.
Through the detailed mapping requirements (1:4800, 1:1200) identified in the TNBMP specifications, several federal mapping programs are benefiting from this large scale data set as well. Leveraging the TNBMP data, a new digital flood map is being developed by the Federal Emergency Management Agency (FEMA) which will improve the ability to manage and mitigate flood hazards in Tennessee. The Census Bureau is using the TNBMP data to help improve their mapping requirements for the 2010 census. Having an accurate census base map is beneficial for programs that rely on federal funding, conducting demographic analysis, and supporting redistricting and voting requirements at the national, state, and local level.